How old is pita from the book summer of the mariposas?

In the book "Summer of the Mariposas" by Guadalupe Garcia McCall, Pita, one of the main characters, is 15 years old. She is the youngest of the five González sisters and plays a significant role in the story as the sisters embark on a journey to Mexico. Pita's age reflects her youthful innocence and the challenges she faces throughout their adventure.